1. Field of the Invention
This invention relates to a novel class of organosilicon compounds. More particularly, this invention relates to a class of organosilicon compounds derived from 1) organohydrogensilanes or organohydrogensiloxanes and 2) novel propargyl esters of carboxylic acids containing a terminal aromatic hydrocarbon radical, where the carbopropynoxy group of the ester and the aromatic hydrocarbon radical are separated by at least two adjacent ethylenically unsaturated carbon atoms. If more than two of these carbon atoms are present they form a sequence of conjugated ethylenic double bonds.
2. Background Information
The photo-induced crosslinking of polyorganosiloxanes obtained by reacting organohydrogensiloxanes with the reaction product of vinyldimethylchlorosilane with an alkali metal salts of cinnamic, beta-(2-furyl) acrylic or alpha-cyano-beta-styryl acrylic (also referred to as 2-cyano-5-phenyl-2-4-pentadienecarboxylic) acid is described by R. Mercier, X. Coqueret and coworkers in the European Polymer Journal, vol. 24, No. 7, pages 639-645 (1988).
In addition to producing quantities of insoluble gel resulting from multiple crosslinks between adjacent molecules, the non-crosslinked by-products produced using the method of Mercier et al. are difficult to separate.
An objective of this invention is to provide novel propargyl esters of the ethylenically unsaturated carboxylic acids described in the aforementioned article by Mercier et al. A second objective of this invention is to provide organosilicon derivatives of these esters that form crosslinked materials upon irradiation with ultraviolet light. Another objective of this invention is to employ these propargyl esters in a method for preparing photo-crosslinkable organosilicon compounds that avoids the shortcomings of the method described by Mercier et al.